Rodless pump



W. N. H UFF RODLESS PUMP oct.. 12, 1937.

Filed May 2l, 1936 gmc/Wto@ A, M, d d d d M/aier /V. fi-uff Mmc/14S,

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Patented Oct.` 12, 1937 UNITED STATES PATENT OFFICE 3 Claims.

This application is a continuation in part of fapplicants applications Serial Nos. 64,920 and 80,211, filed February 20, 1935 and May 16, 1936 respectively, and this invention relates to pumps, especially those used in oil wells and the object thereof is to produce a pump of simple construction, which is durable and ecient.

One object of the invention is to eliminate the use of long lifting rods which in wells of great depth are a great disadvantage.

Another object of the invention is to use pressure generated by a pump at the surface to compress a spring at the bottom of the well and use the energy of expansion thus stored in the spring to force the fluid above the surface. Other objects will appear from the following description.

The invention will be clearly understood from the following detailed description, taken in con- 'y nection with the drawing, in which:

Fig. 1 is a verticalv cross-section with parts shown in elevation,

Fig. 2 is a cross-section looking in the direction of the arrows on line 2-2 of Fig. 1,

Fig. 3` is a, cross-section looking in the direction of the arrows on line 3-3 of Fig. `1,

Fig. 4 is a cross-section looking in the direction of the arrows on line 4-4 of Fig. 1.

The tubing reaching from .the surface to a short distance above the bottom of the well, is

designated by the numeral I. A cylinder, 2, herein called the pumping cylinder, is connected to said tubing by a valved collar 3 to be described later.

To the lower end of this pumping cylinder 2 is connected, by means of a flanged stop collar 4, a perforated .cylinder 5 to the lower end of which a second anged collar 6 is attached as by screwthreads. All of said collars are internally screwthreaded at each end as shown for attachment of the parts, and each of the stop collars has an internal flange for a purpose to be described later.

To the bottom collar 6, is attached any desired footing. At the top of the tubing I is secured a cap I having an internally screw threaded aperture therein.

'I'he collar 3, is of substantial length and near the upper end just below the screw-thread are ngers 3' extending toward the center. These ngers serve as a stop to the upward motion of a floating hollow cylinder 8 described below. Near `the lower end of the collar 3, a valve seat 3" extends toward the center leaving a substantial opening about the axis for the passage of the uid.

The floating cylinder 8 is of much smaller diameter than the tubing, a fact of the greatest im (Cl. 10S-44) portance in the operation of theY device. An eX- ternal flange on the lower end of the floating cylinder forms a valve 9 seating on the seat 3". The movement of the iloating cylinder 8 is limited by contact of the valve 9 with the fingers 3 and With'the valve seat 3".

Within the oating cylinder 8 is a huid-tight piston I0 and attached to this piston preferably by screw threads is a rod I I extending below the collar 3 into the pump cylinder 2. A cage I2 is attached to the lower end of said rod Il and to a valved piston I3 capable of sliding iluid-tight in said pump cylinder. A check valve I4, opening upwardly is confined by the cage I 2 and when seated closes the aperture in valve piston I3.

A second cage I5 is attached to the bottom of the piston and to this second cage a preferably hollow lifting rod I6 is attached. While these various attachments are shown as formed by screw threads, any equivalent means of attachment may of course be used.

The lifting rod passes through the collar 4 and well down into the perforated cylinder 5. On this rod within the perforated cylinder is screwed or otherwise xedly attached, a perforated washer I'I shown in detail in Fig. 4. Y n

A strong heavy coil spring I8 is conned within the perforated cylinder and bears against the perforated washer at one end and an inwardly extending flange on the'collar 6. As this spring reacts with great force after compression, a light cushioning spring I9 is conned in the upper portion of the perforated cylinder bearing on the washer I'I and preferably attached thereto and bearing on the other end, at least when compressed, on the flange of the collar 4.

The apparatus for applying pressure to the uid in the tube A2, releasing said pressure and affording delivery tov the oil is above the surface of the ground, and will now be described. This apparatus comprises a pump 20, single or multiplex and operated by a source of power not shown.

The pumpI has an accumulator 2l and a supply pipe 22 leading from a source of supply 23.

The accumulator may be of anytype and may comprise weights lifted by the pressure or air confined and compressed by the'liquid operated on by the pump.

Communicating with the accumulator is a pipe 25 leading toa valve casing 26 having three lateral openings and arevoluble three-way valve 2'I therein for putting desired openings in cornattached thereto a pipe 28, the lower end of which is attached to the cap 'I. The tubing I is thus in communication with the pump and accumulator in one position of the valve, the delivery being shut off, while in another position, as shown, the tubing I is in communication with the delivery pipe 29, leading to a storage tank S.

The three-way valve is automatically turned through ninety degrees by any convenient mechanism as a link connection 3i shown, or a cam, actuated by any convenient source of power. The pump may be, but is not necessarily, used for this purpose. Ts 32 and 33, respectively, forming parts of pipes 25 and 28 serve to connecta by-pass 3G to said pipes. A check valve 35 opening upwardly in the by-pass serves to correct any tendency to a vacuum above the three-way valve.

The operation of the device is as follows:

After some strokes of the pump the pressure rises, the valve 2l is automatically turned to `place tubing I and the accumulator in communication, the delivery being thereby shut off.

The iluid pressure acting on the piston I i) forces the same downward and alsoA closes valve 9 thus cutting off communication between the tubing I and the cylinders below.

As the piston IIJ descends, fluid must enter the tubing from the source of pressure and the Volume of that fluid will be the internal crosssection of the floating cylinder 8 multiplied by the vertical movement of the piston I3. Piston I3 is moved downward through the same distance as piston I. Valve I4 is raised and fluid flows into the upper part of pumping cylinder 2. The volume of fluid thus entering the upper part of pumping cylinder 2 isequal to the internal cross-section of the cylinder 2 multiplied by the distance through which the piston I3 moves which is equal to the distance through which the piston IIJ moves.

At the end of the downward stroke, the volume of fluid above the piston I3 is increased by the diiference between the aforesaid Y volumes. Through rod I6 and washer I'I, spring vI8 in the perforated cylinder has been compressed by the downward movement of piston I0.

. The pressure on the fluid at the surface of tubing I is automatically released by oscillating the valve to close, the communication with the source of pressure and open the communication with the delivery.

The energy stored in the spring I8, raises the washer II and the piston I3. The valve in the piston I3 closes, valve 9 opens and uid is forcedV through the delivery pipe. As the piston I3 reaches the upper limit of its stroke valve 2T is oscillated to close communication with the delivery pipe and open communication with the source of pressure. The cycle of operations is then repeated.

In the operation of this device the iluid below the pumping piston is never subjected to the pressure of the pressure source and hence oil from the well may ow freely into the perforated cylinder to take the place of that remove'd. Moreover, largely'owing to this fact, the casing usual in the well may if desired, be dispensed with.

Having fully described my invention and the operation thereof, what Iclaiml is:

1. In an apparatus for pumping, a continuous tube, a source of fluid pressure, means for putting said continuous tube alternately in communication with said source of uid pressure and with the atmosphere, a valve seat rigid in the lower part of said continuous tube, a movable hollow cylinder of substantially less diameter than the continuous tube, having a ange forming a valve for said Valve seat, a piston in said hollow cylinder, stop means limiting the vertical movement of said hollow cylinder, a rod connected to said piston, a valved piston slidable fluid-tight in said continuous tube attached to the lower end of said rod, a lifting rod attached to said last named piston, a perforated washer rigidly attached to said lifting rod, a heavy coiled spring bearing against said washer, an internal iiange near the lower end of said continuous tube against which the other end of said spring bears, the portion of the continuous tube below said valved piston in its lowest position being perforated, whereby, on placing in communication the continuous tube and the pressure source, the pistons will be moved downward and the spring compressed and on placing in communication the continuous tube and the atmosphere the spring will be released to expel fluid from the continuous tube.

2.In an apparatus for pumping oil from a well, a fluid-tight structure comprising tubing, a hollow pumping cylinder of substantially the same diameter as said tubing, a collar having an internal valve seat at its lower end and internal stop iingers at its upper end, secured to the lower end of said tubing and to the upper end of said pumping cylinder, a floating hollow cylinder of substantially smaller diameter than the tubing extending into said collar and having a flange at its lower end to seat on said valve seat, a fluidtight piston in said iioating cylinder, a rod depending from said piston and extending into said pumping cylinder, a fluid-tight valved piston in said pumping cylinder and connected to said rod, a check valve on said piston opening separately, a perforated cylinder and a second collar having an internal ange and connecting said perforated cylinder to said pumping cylinder, a lifting rod connected to said valved piston and eX- tending into said perforated cylinder, a perforated washer Xed on said lifting rod, a heavy coil spring in said perforated cylinder bearing at its lower end on said perforated cylinder and at its upper end on said perforated washer, and a lighter coiled spring bearing at its lower end on said perforated washer and at its upper end on the ange of said second collar whereby alternate application and release of pressure at the upper portion of the tubing pumps iiuid from the well.

3. In apparatus for pumping oil from wells, a continuous tube, means for maintaininga uid under pressure, communicating means from said uid under pressure to the upper portion of said continuous tube, a three-way valve in said communicating means for opening said continuous tube to the iluid under pressure or cutting off said continuous tube from said fluid under pressure and opening said continuous tube to the atmosphere and means entirely within said continuous tube for storing the energy given out by the fiuid under pressure when in communication with the continuous tube and applying the same to raising oil in the well when said continuous tube is placed in communication with the atmosphere, and a by-pass around the threeway valve and a check valve therein opening toward said fluid under pressure.

. WALTER N. HUFF. 

